| title: Im2col Layer | |
| # im2col | |
| * File type: `Im2col` | |
| * Header: [`./include/caffe/layers/im2col_layer.hpp`](https://github.com/BVLC/caffe/blob/master/include/caffe/layers/im2col_layer.hpp) | |
| * CPU implementation: [`./src/caffe/layers/im2col_layer.cpp`](https://github.com/BVLC/caffe/blob/master/src/caffe/layers/im2col_layer.cpp) | |
| * CUDA GPU implementation: [`./src/caffe/layers/im2col_layer.cu`](https://github.com/BVLC/caffe/blob/master/src/caffe/layers/im2col_layer.cu) | |
| `Im2col` is a helper for doing the image-to-column transformation that you most | |
| likely do not need to know about. This is used in Caffe's original convolution | |
| to do matrix multiplication by laying out all patches into a matrix. | |